What does it feel like to chop down a tree? Or walk a narrow plank suspended above a deep pit? Stanford University's Virtual Human Interaction Lab can take you there.

Professor Jeremy Bailenson has created a thoroughly convincing virtual-reality environment at the Stanford lab. But what makes it feel so real? The lab uses technology to provide sensory feedback in a couple of different ways. There are devices called "butt-kickers" under the floor that make it shake, 22 speakers provide audio input, and, lastly, there's the head-mounted display that offers a stereoscopic view of the virtual world.

SmartPlanet's Sumi Das tours the lab to learn about the technology and find out how virtual reality is likely to be used in the future.